STS-127 Latest:

Endeavour and her crew have enjoyed a highly successful docked mission, highlighted by the completion of the Kibo laboratory, and five EVAs – the last of which was conducted on Monday.

Following the checkout of Endeavour’s rendezvous tools, the crew departed the International Space Station (ISS) and closed the hatches between the Station and the orbiter.

After undocking Endeavour was commanded through a full lap flyaround of the station – providing stunning imagery of the ISS - ahead of the final separation maneuver/burn.

Flight Day 15 opened with the Late Inspection surveys on Endeavour’s TPS, including her port and starboard RCC (Reinforced Carbon Carbon) wing leading edges, and a full survey of her nose cap. As has been typical for the STS-127 crew, the task was completed two hours ahead of the timeline.

The results of the survey will be downlinked to engineers on the ground, as the DAT (Damage Assessment Team) check for any new areas of damage to the orbiter since the pre-docking inspections. Clearance for the vehicle to re-enter usually takes around 24 hours.

If – in the highly unlikely event – serious damage is found, Endeavour would still be able to return to the ISS, where the crew would take up safe haven until Discovery is launched as the LON (Launch On Need) rescue vehicle.

FD15′s current plan includes a burn known as SEITE-1 (Shuttle Exhaust Ion Turbulence Experiments). An OA (Orbital Adjustment) was required to lower orbit to meet Flight Rule rationale for acceptable relative position of deployable payloads with ISS.

Those payloads are DRAGONSAT and ANDE-2, which are currently housed in Endeavour’s payload bay. They will be deployed on Flight Day 16.

“DRAGONSAT: The Dual Autonomous Global Positioning System (GPS) On-Orbit Navigator Satellite (DRAGONSAT) payload is a new endeavor into establishing autonomous spacecraft rendezvous and docking capabilities and is primarily focused on data collection for future control algorithms,” noted FRR documentation on L2.

“The payload is cosponsored and operated by Texas A&M University and The University of Texas at Austin.

“ANDE-2: The Atmospheric Neutral Density Experiment (ANDE) ‘Risk Reduction’ (RR) was first flown on STS-116 as one of the Space Test Program – H2 (STP-H2) experiments.

“Similar to its predecessor, ANDE 2 will be flown on a shared flight as a secondary payload by the National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD) STP on STS-127.

“The two goals of the ANDE 2 mission are to provide high quality satellites with stable and well-determined coefficient of drag, for calibrating techniques and models for precision orbit determination; and to provide atmospheric composition for validating Air Force sensors.”

STS-127 remains on track for a Friday landing at the Kennedy Space Center (KSC), with the Mission Management Team (MMT) discussing the landing opportunities for the first tine, now that Endeavour has departed from Station.

“No issues were raised at the meeting. The weather office provided a preliminary look at landing weather for Friday and Saturday,” noted MMT notes on L2. “They are predicting that drier air will be coming in from the Southeast and assist in setting up good landing weather.

“There is a slight chance of showers at KSC on Friday and Saturday but the weather generally looks favorable at this time. Entry Flight Director Mr Lunney will provide the entry briefing at the MMT tomorrow (Wednesday).”

ET-131 Foam Loss Investigation:

As the PRCB (Program Requirements Control Board) prepare to meet on Thursday for STS-127′s IFA (In Flight Anomaly) review – a key milestone that aids the next flight’s Flight Readiness Reviews (FRRs) – the topic of ascent debris is homing in on a root cause for the ET-131 foam loss events.

ET-131 lost several areas of foam from its Intertank region during ascent. None of the liberation events caused anything more than cosmetic damage to Endeavour’s starboard Chine.

Pull tests were carried out on ET-132, set to fly with Discovery on STS-128, all of which came back with good results on the adhesive properties between the foam and the tank’s structure.

Those results add confidence that ET-131′s foam loss events were a one-off, and are unlikely to repeat on ET-132 or other downstream tanks.

“Foam Loss Investigation Team Update: The Fishbone Team worked all last week and through the weekend looking to identify the possible causes and failure modes,” noted an update on the latest Shuttle Standup/Integration report on L2.

A candidate for the foam loss has been found, specifically dust, or substrate contamination, on the tank’s structure ahead of the application of foam.

“The failure mode is being attributed right now to the low-to-no foam bottom-line integrity in their focus and on the failure modes observed on ET-131, which was foam loss with exposed primer. No one has said they didn’t see any primed surface yet.

“Right now the most likely causes are substrate contamination (e.g., dust) prior to foam application. Looking at cleaning and primer touch up processes, which all are in Cell G (at the Michoud Assembly Facility).

“Other observations/findings to date are: No obvious violations to process found in paperwork. Some of the cleaning techs during that time were new employees, although certified and trained. Had a large amount of primer touch up.

First intertank sprayed after return-to-flight. Tank sat around plant and was moved several times. Did paper spray on tank prior to checking out the cell.

“Later this week, are looking to have a package to bring forward on the most likely causes to start briefing the communities and the independent review team.”

It is understand that a root cause is not required for STS-128′s Flight Rationale at the FRRs, although understanding the reasons behind the foam loss would allow for the swift closure of the IFA.

STS-128′s SSP (Space Shuttle Program) FRR will take place at the Johnson Space Center on August 11 and 12, before the STS-128 Agency FRR, on August 18, will confirm the launch date.

L2 members: Documentation – from which the above article has quoted snippets – is available in full in the related L2 sections, now over 4000 gbs in size.

Related posts:

1. Endeavour and her SCA piggyback ride arrive in Louisiana, via JSC flyover The Shuttle Carrier Aircraft (SCA) and Endeavour departed from Edwards...

ET-131 Event – ET-132 Investigation:

Foam on the intertank region of the ETs is added via an automated application process at the Michoud Assembly Facility (MAF) in New Orleans.

Due to its placement in-between the LH2 and LOX tanks, the region usually avoids the large foam liberation events due to the relatively benign thermal conditions – compared to foam directly associated with the super cold temperatures of the propellant tanks.

A condition known as “popcorning” can occur, but holds no threat to the orbiter, due to the small mass associated with such liberations, and the late stage of ascent during which this condition usually occurs.

The mechanics of foam loss relates to when TPS cell pressure at substrate exceeds bond adhesion strength. Voids in the foam can also suffer from “cryopumping” – although such events have not been seen on the intertank.

What is for certain is the complex material sciences associated with the control of TPS foam loss during the pressures of launch, which is near-impossible to avoid. Modifications to the tanks since Columbia have mainly focused on reducing the most “at risk” areas of foam, thus removing the debris threat.

Although it was late in ascent when Endeavour’s ET-131 intertank started to shed foam - thus holding no serious debris impact threat to the orbiter due to the lack of atmosphere that would result in a high velocity impact – engineers are looking into its root cause.

Currently, that root cause remains elusive, with the initial conclusions focused on a potential issue with the adhesive/bond properties between the foam and the intertank’s structure. That in turn placed doubts on the next tank set to fly, ET-132 – kick-starting an investigation to gain confidence the same event was unlikely to occur during next month’s launch.

“ET-132 Bond Adhesion Evaluation: Purpose: Provide plans and obtain approval to inspect ET-132 / STS-128 Intertank TPS (Thermal Protection System – Foam) at KSC. Additional data needed to provide confidence in the as-sprayed TPS integrity,” noted an overview presentation available on L2.

Interestingly, the presentation appears to cover other foam loss events from ET-131, such as the debris shower noticed at T+104 – which was initially claimed as not originating from the intertank, when it caused cosmetic damage to Endeavour’s starboard Chine area. However, this is now unclear.

“Background: Multiple / unexpected Intertank TPS loss events observed on ET-131. 1st observation occurred at around 104 seconds MET (Mission Elapsed Time). Losses occurred around entire periphery of tank. Majority of foam loss events appear to extend to the primed substrate.

“Indication of inadequate TPS adhesion due to unique processing anomaly. Timing (> 100 secs. MET) consistent with physics-based understanding of bond adhesion failure mode. Losses occur due to vacuum / ascent heating load affects at TPS / primer bond.”

Root cause may have been easier to pinpoint had a manufacturing change been noted by MAF in relation to the intertank. However, the presentation confirms no changes to the application of the foam have been made.

“No engineering changes (design or process) to Intertank acreage for ET-131 / STS-127 or ET-132 / STS-128. NCFI 24-124 TPS applied using automated spray process. Majority of material power machined (optimize weight) and perforated (+Z, debris minimization).

“Majority of material thickness around 0.5” (nominal). Nominal as-built density around 2.6 pcf. On-part lead-in/out bond tension tests performed in cryo regions near flanges (>30 psi required).”

ET-132 Pull Tests:

Already inside the Vehicle Assembly Building (VAB), mated with the twin Solid Rocket Boosters (SRBs) and awaiting the arrival of Discovery for mating, access to ET-132 is already in place.

This has allowed the majority of the pull tests – used to check the adhesive properties on ET-132 – to take place, ahead of scaffolding being installed for access to the remaining test areas on the intertank.

“Plan focused on determining root cause in parallel with performing tests/inspections of as-built hardware,” added the presentation. “Planning bond adhesion pull tests on ET-132 / STS-128 to provide confidence in Intertank TPS application integrity.

“Twenty-six (26) tests planned with samples from each panel (8 panels). Majority of tests (12 of 26) being performed on three (3) +Z panels. Locations selected based on observed ET-131 performance and debris potential (i.e. CDZ).

“Tests planned on stringer top and sidewall leading / trailing edges. Tests provide best method to determine integrity of bond strength. Additional testing may be required based on ET-132 process data review.”

As of Tuesday morning, 18 of the 26 pull tests have been conducted, with results showing encouraging signs that ET-132′s intertank has the required adhesive strength between its structure and TPS foam.

“Of the 26 test sites 18 were completed (all the walk up access). All tests were 100 percent cohesive failures (broke in the foam – which is good news) and the pull numbers ranged from 14.25 to 84.9 psi with only two values below 43.77,” noted engineering logs on the test (L2).

“The two that broke between 14 and 16 and these had some issues during the testing (the cores were not completely perpendicular, and the plug was bonded slightly crooked) and could have technically been declared a no test.”

Access was being built via scaffolding to conduct the remaining tests – now expected to show the same positive results – while repairs on the previous test areas are soon to take place.

“High Crew is in the process of completing installation of scaffolding this morning. 13 of the 18 locations are being prepped for repair,” added STS-128 processing information for Tuesday morning (L2). “Three require additional photo work and two others are under Engineering Evaluation.

“USA (United Space Alliance) will begin repairing the 18 locations starting with any primer touch up that is required, less the two areas that had lower pull values.”

Should the tests continue to show good results, shuttle managers will have the confidence to clear the tank to fly near the end of August.

UPDATE: All 26 Pull Tests now conducted by Tuesday night, all with good results.

“Path to Flight Rationale for STS-128 / ET-132: Root Cause is isolated to ET-131 with positive test / inspection results. Similar foam loss not expected during STS-128,” noted the presentation based on good pull test results.

However, even the worst case results would have only incurred around a few weeks worth of delay to the schedule, due to the low threat from such foam liberations from the intertank during ascent.

The only requirement would have been to “remove and replace suspect NCFI (foam) with BX manual spray,” which can be carried out inside the VAB.

Other work taking place relates to the Damage Assessment Team (DAT) creating models to show the main flow paths of foam liberations from the intertank, and the worst case damage such a liberation could threaten.

The results will be overviewed at the STS-128 Space Shuttle Program (SSP) Flight Readiness Review (FRR) next month.

ET-132 Damaged During Tests:

As luck would have it, the tests caused new damage to ET-132, when part of the new scaffolding fell on to the tank. Thankfully the damage is minor.

“During build up of scaffolding on platform E around the external tank, a technician was tightening a tube-lock for a handrail,” added Tuesday processing information. “The tube-lock broke and fell from the scaffolding, impacted the ET and landed on B platform roof directly.

“In the area contacted, there is minor damage to a stringer just below the flight door. Dimensions and repair technique to be addressed in PR (Problem Report).”

This incident should not cause additional delays to the rollover of Discovery, which is tracking both the finalization of testing and subsequent repairs to ET-132, and the completion of repair work that is taking place on Pad 39A’s flame trench, which lost some of its refractory concrete during Endeavour’s launch.

“Pad-A: MLP-3 (Mobile Launch Platform) transfer to the East Refurb Site is complete. Flame trench repairs continue; completion is expected by the end of the week,” noted processing information, which confirms the Pad will be ready well ahead of Discovery’s current date for rollout on July 30 – based on a Thursday rollover to the VAB for Discovery.

“The STS-128 Shuttle Final Countdown Phase Simulation (S0044) for team certification is scheduled for today,” added Tuesday processing information.

“The following operations have been rescheduled to support inspections resulting from the STS-127 launch debris events: Rollover to VAB for integration is scheduled NET July 23. Shuttle Interface Testing will pickup immediately following Orbiter/ET mate. Payload transport to Pad-A on July 27. SSV (Space Shuttle Vehicle) rollout to Pad-A on July 30.”

Discovery is being prepared for a 13 day, 3 EVA, mission to the ISS that will include the flight of the TriDAR AR&D Sensor Detailed Test Objective (DTO), the next Boundary Layer Transition (BLT) DTO, and the first flight of the OI-34 flight software. The mission was swapped from Atlantis to Discovery, following the changes in the 2009 manifest.

Also riding uphill with Discovery will be a new crew member for the ISS – Nicole Stott – as well as MISSE (Materials on International Space Station Experiments) 6A and 6B, SIMPLEX, MAUI, and SEITI.

However, the primary payload for Space Shuttle Discovery will be the MPLM (Multi-Purpose Logistics Module) Leonardo, and the Lightweight Experiment Support Structure Carrier with an Ammonia Tank Assembly.

L2 members: Documentation – from which the above article has quoted snippets – is available in full in the related L2 sections, now over 4000 gbs in size.

No related posts.

STS-127 Mission:

STS-127 is the 127th space shuttle flight, the 29th to the station, the 23rd for Endeavour and the third in 2009. Endeavour’s flight will deliver the final components of the Japan Aerospace Exploration Agency’s (JAXA) Kibo laboratory to the ISS.

The 16-day mission will include five spacewalks and the installation of two platforms outside of the Japanese module. One platform is permanent and will serve as a type of porch for experiments that require direct exposure to space. The other is an experiment storage pallet that will be detached and returned with the shuttle.

During the mission, Kibo’s robotic arm will exchange three experiments from the palette to the platform. Future experiments also can be transferred to the platform from the inside using the laboratory’s airlock.

Endeavour also will deliver Tim Kopra – who will stay on Station until STS-128, while Koichi Wakata – who arrived on the orbital outpost with Discovery on STS-119 – will return to Earth at the conclusion of STS-127.

STS-127 S0007 Launch Countdown Flow:

Processing had been proceeding to plan, with RSS retract occurring exactly on the timeline at 11pm Friday night.

“Orbiter: OV-105 / ET-131 / BI-138 / RSRM-106 (Pad-A): Launch countdown is in progress. PRSD (Power Reactant Storage and Distributation) Cryo Load complete,” noted S0007 processing information on L2.

“OMBUU (Orbiter Mid Body Umbilical Unit) de-mate complete, SSME (Space Shuttle Main Engines) final preps and TSM (Tail Servicing Mast) securing in work. Comm Activation was completed on Friday.

Only two minor items made the IPR (Interim Problem Report) list, one relating to the TAL (Transatlantic Abort) site – which will be resolved by Saturday morning.

“During S0027 preps in Istres, France: Istres Backup MSBLS (Microwave Scan Beam Landing System) indicating Azimuth and Elevation Alarms,” added processing notes. “Transmitter is being replaced and will be complete Saturday (6 hour time difference). Constraint is S0007.200 15-3.”

The other issue related to an engineer accidentally catching a switch in Endeavour’s crew cabin – which is usual, due to the tight workspace technicians have to negotiate on the flight deck.

“During Surveillance, inadvertent switch throw following completion of ECLSS (Environmental Control and Life Support System) switch config per S0007.400.

“Panel L4 Row J AC3, HUM SEP and IMU (Inertial Measurement Unit) signal conditioners were inadvertently closed when engineer was egressing the commander seat.

“These breakers are OPEN for flight and are located next to each other. Will have them repositioned OPEN per the IPR.”

Upcoming processing milestones included the activation of the Fuel Cells at 4:34 am local time (complete), prior to the countdown entering the 2-hr hold at T-6 hour mark at 8:14 am (complete).

The MMT had to wait until 10 am local time for a weather update to aid their evaluations into up to 11 lightning strikes on the pad overnight, in order to give a go for tanking.

However, with more data required on Endeavour’s electrical systems, managers decided to hold for 24 hours, with another attempt to take place on Sunday.

“Took eleven strikes within the 0.3 miles of the pad,” noted MMT chair Mike Moses. ” If a strike comes into the .3 NM radius, kicks off a formal review of the strike, determine if the strike was big enough to declare a lightning event, then we go from there. 

“Just because we had strikes in the .3 NM, doesn’t mean it was a formal event.”

The Space Shuttle Main Engines (SSMEs) and External Tank have had their systems cleared. However, the orbiter and the Solid Rocket Boosters (SRBs) are still being evaluated.

ET-131 Foam Crack Status:

Managers have decided against the removal of an area of cracked foam from ET-131′s LO2 Feedline, after it was deemed such a procedure could actually increase the debris potential during Endeavour’s ascent.

“Discussion Item: During STS-127/ET-131 post tanking test walkdown, crack observed on aft face of XT1377 feedline strut. Potential debris risk (estimated mass 0.0033 lbm, foam only),” noted a presentation on the crack, available on L2.

“Background: Similar condition previously observed and accepted on STS-51 / ET-59 (09/1993) and STS-121 / ET-119 (07/2006). STS-121 cracked TPS observed during scrub turnaround, foam fell off prior to launch. Foam mass was below specified requirement (.0057 vs .013 lbm).”

The cause of TPS crack is understood to be related to the third detanking of ET-131 – which occurred after the successful tanking test at the start of the month.

“Ice formed during tanking creates an interference at the strut to monoball interface,” explained the presentation. “Loads induced during detanking cause cracks. Inherent to the design.”

The initial plan was to trim the area of TPS, thus removing the foam that has the potential to liberate during ascent. However, the decision to fly “as is” was made easier by confirmation such a foam liberation would hold no threat to Endeavour, due to its small mass.

“Recommendation: Use as is. Supporting Rationale: Explained condition, Ice / Debris. Inspection Criteria and is acceptable during launch count. Minimal debris potential assuming TPS liberates with attached ice (~0.006 lbm),” added the presentation.

“Combined mass below documented risk assessment mass for TPS only (0.013 lbm). Debris risk is low per SE&I (Systems Engineering and Integration) assessment (tile risk only / no risk to RCC – Reinforced Carbon Carbon).

“TPS liberation does not impact structural requirements. TPS only required to preclude ice formation. Procedure for TPS removal not defined, vetted, or practiced by technicians. Risk of collateral damage during removal process

“Removal of TPS would increase ice mass and ice debris potential. Thermal analysis predicts ~0.017 lbm increase (0.019 lbm already assumed). Cracked TPS material likely to liberate and could impact Orbiter tile (On-orbit MMT item). Same risk for strut TPS at XT 1129 and XT 1624.”

Weather Situation:

Endeavour has a four day launch window, prior to a standdown to allow for the launch of the next Russian Progress resupply ship. The opening attempt for Endeavour on Saturday only has a slim chance of finding acceptable weather conditions, with a 60 percent likelihood of thunderstorms in the 20 mile radius.

“The surface front will be in the Central Florida area on Saturday. The upper-level trough will begin to migrate northeast, but early afternoon showers and thunderstorms will develop along the sea breeze, and the front in the area will act as an added trigger for these storms,” noted the USAF weather forecast for the area.

“Most of the activity will occur before the launch window, but weather may still be in the area by launch time. Our primary concerns for launch are showers and thunderstorms within 20NM of the Shuttle Landing Facility (SLF) and anvils.”

Such has been the poor weather in the KSC area, a lightning strike has hit the ground within five miles of Pad 39A on every evening since July 3rd. A direct strike was suffered by the pad on Friday, hitting the Fixed Service Structure (FSS) mast – which resulted in no ill effects to Endeavour.

The weather forecasts show a slight improvement for a Sunday launch attempt.

This article will be updated during the countdown. Refer to live update pages – linked above – for up to the second updates.

L2 members: Documentation – from which the above article has quoted snippets – is available in full in the related L2 sections, now over 4000 gbs in size.

No related posts.

STS-127/Endeavour Processing Latest:

Endeavour remains on track for the July 11 launch from Pad 39A, with no serious issues being worked on the vehicle. The STS-127 crew – led by Commander Mark Polansky – also made their journey from Houston, arriving at the Kennedy Space Center (KSC) on Tuesday afternoon.

Over the holiday weekend, S5009 operations – including Range Safety checkout and GUCP (Ground Umbilical Carrier Plate) ordnance connect – were completed, while the majority of recent flow work involved S0071 (Hyper loading/pressurization) operations, which have also been completed.

“S0071 Hyper Pressurization: OMS/RCS (Orbital Maneuvering System/Reaction Control System) Helium Regulator Lockup was completed. MPS/SSME (Main Propulsion System/Space Shuttle Main Engine) Helium Tank Fill is complete,” noted Tuesday processing information on L2.

“OMS/RCS GHe/GN2 Stage 1 Press is complete. S0007.100 Launch Countdown preparations continue. Two waves of LH2 replenishment were successfully completed yesterday.”

S0007 Launch Countdown Call To Stations is set for Wednesday, July 8 at 2130 EDT, with the milestone checkpoint of the L-1 MMT briefing scheduled for July 10 at 0900 EDT.

“It is good to have everyone back from the July 4th weekend. Hope that everyone had the chance to rest and visit with their families,” added Shuttle Manager John Shannon on the latest Standup/Integration report on L2.

“The STS-127/2JA flight will be a long mission, with many objectives to accomplish. Everyone needs to be ready for launch and to be sure the mission is properly executed.”

External Tank Inspections:

Following ET-131′s successful tanking test on July 1, pad and ET engineers have completed a full evaluation of the tank’s TPS, providing a list of items that may be of interest, or may require repair ahead of launch. Three such areas were found on the tank, with repairs taking place throughout Tuesday.

“An External Tank LO2 feed line inspection was completed yesterday with three foam discrepancies observed,” noted Tuesday processing information. “Two of them will require no work (ET-131-TS-0020/0021). ET-131-TS-0019 was generated for a 2.5” piece of cracked foam that will require the LO2 feed line platform and diving boards to repair.”

Expanding on the flow update, inspection logs and photographs – acquired by L2 on Tuesday morning - outlined the ET areas of interest in greater detail.

“Post Tanking LO2 Feedline Inspection: Inspection was performed on LO2 feedline for STS-127/ET-131 to assess the potential debris noted behind station XT1129 on the Post Tanking Scrub Walkdown and to quantify any chaffing on the LO2 Feedline Brackets, LO2 Feedline and the Intertank.

“XT-1115 (Intertank to LO2 Feedline): There are several areas of chatter/chaffed foam on the Intertank that appear to be within the bounds of (requirements) and no loose material present. There was little to no change to the area as observed on the Post Drain Walkdown.

“An inspection behind the feedline was performed and there was no chatter marks observed on the LO2 Feedline. Will be initiating a PR (Problem Report) on this item and we will be processing a MRB (Material Review Board) for ‘use as is’”

“XT-1129: Removed all loose debris and inspected the location and the area had minor amount of foam chatter that was not apparent prior to the Tanking. Will be initiating a PR on this item and we will be processing a MRB for ‘use as is’ to assess the damage and any potential debris concerns.”

The main area that underwent evaluation is on the inboard LO2 Feedline Bracket Strut, which has two cracks on its aft face. Engineers are likely to work a procedure to remove the damaged materials, eliminating the potential for it to become a debris concern during launch.

“XT-1377: The larger of the cracks is emanating from a point on the aft side of the strut approximately two inches from the +Z end. The smaller crack is located on the chamfer at the +Z end of the strut.

“The larger crack appears very similar to the crack that was observed on STS-121/ET-119 prior to the piece liberating and being discovered on the MLP (Mobile Launch Platform).

“The local consensus is to process an MRB to remove the loose material to alleviate the debris concern, assess any icing concerns, and essentially fly in the same configuration as STS-121/ET-119.

“Will be coordinating the disposition with ET Project and we will have MRB approval prior to any foam removal. The PR has been initiated. All other Feedline Bracket locations appear to be in nominal condition.”

LH SRB Crack/Chip:

During the walk-downs last week, engineers spotted what appears to be a paint chip on the LH (Left Hand) SRB, located a couple of inches above the field joint. Following the configuration of safety ropes and access platforms, repair work is expected to be completed by Wednesday morning.

“During a surveillance walk down of the BI-138 Booster set located at Pad-A it was observed that a possible impact of the LH Booster by an unknown source could have occurred,” noted an engineering report on L2.

“A suspect mark on the LH Booster topcoat was noted at approximately the 22 degree location on the 155 foot level. The size of the ‘mark’ is guessed to be .15 X .005 inches.”

Other notes class the mark – caused by windstorm on June 26 – as “hard to identify”, though it will be repaired ahead of flight, given the confidence that the damage is only cosmetic.

“An issue in work for STS-127/2JA concerns loss of coating on the left-hand center-forward segment, resulting from a windstorm on June 26. This is a very small area, but it is being investigated,” added notes.

“Photos were taken of the area, but the clarity and detail of the pictures cannot indicate if the area is in fact an impact mark or an unknown foreign material.

“Once we gain access, a sample will be taken of the area, any raised metal will be sanded and removed, Eddy Current will be performed, and primer and topcoat will be applied.

“High Crew has installed access to the SRB anomaly on 155′ level of Pad A. The SEAT has assessed the access and pending installation of an additional support to resist horizontal loads (expected 2nd shift), it will be ready for use.”

L2 members: Documentation – from which the above article has quoted snippets – is available in full in the related L2 sections, now over 4000 gbs in size.

No related posts.

 
ET-131 will ride with Endeavour, currently tasked with both the STS-400 LON (Launch On Need) support for Atlantis’ STS-125 mission to the Hubble Space Telescope – currently scheduled for May – and Endeavour’s primary STS-127 mission.

STS-127, currently tracking a June 13 launch date, will complete the assembly of the Kibo Laboratory complex, with Endeavour carrying an array of payloads that will require a 15 day mission with five baselined EVAs.

Aside from installing the Japanese Experiment Module – Exposed Facility (JEM-EF), Endeavour’s crew will be tasked with replacing six batteries on the P6 truss.

The tank’s arrival was ahead of the required timeline by a couple of weeks, which earned thanks from shuttle manager John Shannon, who “congratulated the team at MAF for all of their hard work on getting this tank ready ahead of schedule.”

With four other tanks undergoing major production at the Lockheed Martin run facility, MAF find themselves in a much more comfortable position – compared to previous years since Return To Flight - despite the heavy schedule of downstream flights in 2009 and 2010.

However, ET program manager Mark Bryant noted his insistence that the engineering workforce should continue to ensure the tanks leaving the facility are of the best possible quality, regardless of the high flow of tanks required to complete the current shuttle manifest.

“It’s an ambitious schedule that will require continued high levels of performance from the team,” said Bryant, “performance that we are demonstrating every day in producing safe, high quality tanks.”

All four tanks used in the 2008 shuttle missions lacked any major foam losses, with STS-126′s year-closing flight with Endeavour enjoying a ride uphill with what is widely regarded as the cleanest tank to have ever flown during the eight and a half minute ascent into orbit.

The performance of the tank, ET-129, earned thanks for the MAF workforce from Endeavour’s crew, during their post flight visit to New Orleans.

“I got to space because of the hard work of each of you. It’s a team effort,” said STS-126 mission specialist Heidemarie Stefanyshyn-Piper. “I was just the lucky one to take the ride up.

“Every job here at Michoud contributes to the success of a mission, not just the folks physically working on the tanks. From the person who prepares meals through the purchasing department, I thank you for your work and contributions to mission success.”

ET-129 proved to be a major effort ahead of its trip to Florida, with the tank eventually shipped ahead of its previous planned schedule in support of the Space Shuttle Program (SSP) options to accelerate STS-125, to be used for adding earlier launch opportunities for STS-126′s short launch window in November.

Due to the on orbit issues with the Hubble Space Telescope (HST), STS-126 jumped a launch slot. However, the initial push to ship ET-129 to KSC in a timely fashion involved a three shift, round-the-clock, drive at MAF – which was also recognized by their NASA paymasters.

“Looking out across the crowd, there are a lot of folks here who put in a lot of dedicated hours and a lot of hard work to get ET-129 together and prepared for its launch,” said Chip Jones, NASA Michoud chief operating officer during a general assembly at the plant.

“On behalf of NASA, I would like to personally thank you for your dedication.”

Despite the successful turnaround into a smooth schedule for the upcoming tanks, challenges remain, not least via a potential extension of the shuttle manifest, and the requirement to create space for new tooling that will be used to build the Ares vehicles for the Constellation program.

ET-138 was set to be the last shuttle tank to be produced by MAF. However, with STS-134 close to being officially added to the manifest, managers have been working a plan to refurbish ET-122 – which was damaged during Hurricane Katrina, when it was hit by falling roof panels in the facility’s Cell A.

NASA has authorized Michoud Operations to perform a limited scope of work on ET-122 through April, with engineers inspecting the tank for damage to its pressure vessels and metal substrate.

“Transportation and Handling moved the tank to Bldg 420 just before Christmas, and technicians will perform shearography to inspect for possible concrete chips in foam,” noted MAF information.

“Technicians will also remove and replace Liquid Oxygen and Liquid Hydrogen umbilicals; perform borescope inspections; strip foam from damaged areas of the Intertank; and clean its internal surfaces.”

Currently, the plan is to make this tank available for LON requirements associated with STS-134′s mission to carry the Alpha Magnetic Spectrometer (AMS) to the International Space Station (ISS) – pending funding.

Also, in pre-emption of a possible extension being approved this summer, MAF have completed initial work on two additional tanks, ET-140 and ET-141, alongside a tooling plan that would allow utilization of new Ares machinery on additional shuttle tanks, as and when required.

The next tank due out of MAF is ET-132, which will fly with Discovery on STS-128′s logistics mission to the ISS. The tank is currently in final assembly, with “everything is proceeding nominally.”

L2 members: All documentation – from which the above article has quoted snippets – is available in full in the related L2 sections, now over 4000 gbs in size.

No related posts.

The STS-119 stack is being worked through Orbiter/ET mate (S0004 operations) since Discovery was transitioned over to High Bay 3 (HB-3) inside the Vehicle Assembly Building (VAB), with soft mate and hard mate going to plan – bar the issue with the umbilicals.

“Soft-mate of the forward and aft was completed at 2034 EST Thursday. Hard-mate and final torque of the forward and aft orbiter/ET attach points is complete (prior to torque measurements),” noted processing information on L2, which added progress towards launch at Pad 39A.

“Hypergolic preparations for propellant loading at Pad A are in work. APU Carts have been transported to FSS 135′ level and OMS/RCS flow meter R&R is complete. Cryogenic propellant storage tank (LH2) replenish has begun in preparation for launch. Payload transfer to Pad A preparations has begun.”

Currently, the Shuttle Interface Test is set to take place on Sunday, along with preparations to transfer STS-119′s payload to the Payload Changeout Room (PCR).

“Weekend Work: Shuttle Interface Test (S0008) Call to Stations is planned for 0400 EST, Sunday morning,” added processing information. “Transfer Payload to Payload Changeout Room (S0600.001) Call to Stations is planned for 1700 EST, Sunday evening.”

Following hard mate operations, three umbilical studs are tensioned on each side of the tank – LH2 and LOX sides – two of which are drawn together between the External Tank and the orbiter.

This operation has been an issue free operation for over 100 matings. However, as seen on a couple of recent matings, problems were again encountered with over-tensioning.

During mating and connection operations, MEQ engineers monitor the studs to ensure they are correctly tensioned during the procedure. They observed problems on the LH2 side, as the stud torque was deemed to be above maximum allowable levels.

Engineers stopped the operation (see image left from L2′s live STS-119 processing coverage) and asked the hydraulics engineers to make sure the hydraulic retract actuators were free and not locked up. The LO2 side was proceeding nominally at the time. Troubleshooting was continuing through Saturday, although it is not known if there will be a delay to Sunday’s S0008.

No root cause has been found as to the reason why the studs are over tensioning during this operation – which was most notable on Atlantis’ mate with ET-127, when an umbilical plate was damaged due to the issue. While Discovery is now using that same tank, the problem is believed to be on the orbiter side.

UPDATE: LO2 and LH2 umbilical mates and stud tensioning and verification are complete as of early Saturday afternoon, allowing the on schedule start to S0008 operations.

Meanwhile, good news is being noted on the effort surrounding the Flow Control Valves – which will be replaced on Discovery shortly after she arrives at the pad, following the problem observed on Endeavour during STS-126′s launch.

“Had a good session on FCV poppet anomaly. Delivered the spare poppets to Huntington Beach, and examination is complete. Electron-microscope investigation reveals no cracks in these units,” noted JSC Orbiter on the latest Shuttle Stand-up/Integration report on L2. “This is very good news, as they are scheduled for installation for the next flight.

“Will complete dye-penetrant analysis, and expect to have the parts back to vendor for reassembly. Delivery to KSC will follow. Received a good status from M&P area; they believe the issue is high-cycle fatigue, but testing will continue. Are pursuing testing to better understand effects of H2 embrittlement and how this would affect propagation of the flaw.”

The Orbiter Project – also at the Johnson Space Center (JSC) – continued the positive tone on the path towards a resolution.

“Had good meeting. To date, we have examined eight poppets that have flown (three from OV-104 (Atlantis), two from OV-105 (Endeavour), and three spares). All we are seeing is a machining/grinding artifact of roughly four mils. This is an order of magnitude less than the 40 mils seen on the failed items.

“There are 22 spare poppets that are unflown. These will be examined for machining artifacts. If what is found on the unflown items matches the others that have been studied, it will provide additional confidence that we are not growing these cracks in flight. Analysis is in work. Results are expected mid-February. The next meeting on this topic will be next Tuesday.”

Discovery’s two sisters are enjoying smooth proceeding flows, with Atlantis patiently waiting for confirmation of a May launch date for the realigned STS-125 mission to the Hubble Space Telescope.

Endeavour, however, is at a busy stage of her processing, which was marked by the removal of her three SSMEs (Space Shuttle Main Engines), following their role on STS-126.

“SSME (Pratt & Whitney Rocketdyne/KSC): All three engines have been removed from OV-105,” noted the Stand-up. “Engine number three from OV-105 has been reassigned to Discovery.”

In other notable processing work, Endeavour’s MO10W Panel O2 System number 2 line is undergoing replacement, following the temporary installation of a jumper line for one mission – required after an anomaly was noted ahead of last year’s mission.

The new MO10W is installed; with engineers now working to reconnect all the associated fittings.

Other work taking place revolves around checking Endeavour’s TPS (Thermal Protection System), in order to plan out any required repairs and replacements. The current stage of that process involves thermography on chin panel and nose cap – which has been completed.

Endeavour is being readied for the multi-role of once again being the STS-400 LON (Launch On Need) shuttle in support of STS-125, and her primary mission of STS-127. The tank Endeavour will use – ET-131 – is enjoying a smooth processing flow at the Michoud Assembly Facility (MAF) in New Orleans, and remains on schedule to support.

A decision on aiding Ares I-X’s launch date by utilizing Pad 39A for both STS-125 and STS-400 – as opposed to holding on to the current plan of hosting STS-400 on Pad 39B – is still pending.

“A meeting was held to discuss single versus dual pad Probabilistic Risk Assessment (PRA),” added the Stand-up. “Agreement on methodology was reached, and input will be incorporated into the presentation. The packet will be ready for discussion soon.”

Should managers decide that it isn’t viable to place STS-400 on Pad 39A very shortly after STS-125 launches, Pad 39B will not be handed over to Constellation until at least mid-May. Such a decision would likely delay Ares I-X – due to pad work required for the test flight – from its July launch target, to around October.

L2 members: All documentation – from which the above article has quoted snippets – is available in full in the related L2 sections, now over 4000 gbs in size.

Related posts:

1. Dual flow ballet for Endeavour and Atlantis – De-stack debate Preliminary milestone schedules have been created for the complex dual...